D.J. Baxendale had a dominant 19-inning pro debut after going to the Twins in the 10th round of the 2012 draft out of the University of Arkansas and began his first full season by jumping all the way to high Single-A, where he went 7-0 with a 1.10 ERA in nine starts. That earned Baxendale a lot of attention and a quick promotion to Double-A, but he allowed as many earned runs in his first start there as he did combined in nine starts for Fort Myers.

Overall in New Britain he got knocked around for a 5.63 ERA and .293 opponents' batting average in 16 starts to provide a reminder that college pitchers thriving at rookie-ball and Single-A tends not to mean much of anything. Baxendale throws strikes and works mostly in the high-80s with his fastball, so it's not surprising that he ran into a wall against more experienced Double-A hitters after carving up the low minors.

Another worry is that he's an extreme fly-ball pitcher and that became an issue for the first time in New Britain, where he allowed 13 homers in 93 innings. Fly balls and high-80s fastballs are a bad combination, although it's worth noting that Baxendale reached Double-A very quickly at age 22. His raw stuff seems unlikely to ever translate into many missed bats, so Baxendale's control may determine his big-league chances. So far he's walked just 35 batters in 169 pro innings.

Last year the Twins' biggest international splash was spending $1.4 million on 16-year-old Lewin Diaz, a 6-foot-4 first baseman from the Dominican Republic. Ben Badler of Baseball America, whose coverage of foreign prospects is the most informed and thorough anywhere, ranked Diaz as the 15th-best international player available and wrote that "his value is all in his bat" and his "big, lumbering body ... could end up along the lines of David Ortiz physically."

Having an Ortiz build unfortunately doesn't necessarily mean having an Ortiz bat, but Badler reported that Diaz has "good bat speed and flashes some of the best raw power in Latin America during batting practice." However, he also noted at the time of the signing that Diaz "doesn't bring the same loft power against live pitching" and "will have to make adjustments for his power to play in games."

Jesse Sanchez of MLB.com ranked Diaz as the 10th-best international prospect, writing that "scouts love the big left-handed hitter's stroke at the plate and his body reminds many scouts of Ryan Howard." When a baby-faced 16-year-old is compared physically to Ortiz and Howard he's going to be a massive adult some day, so not surprisingly Diaz has sub par speed and projects as a first baseman. In other words, the Twins are betting on him developing huge power.

When the Twins traded Drew Butera to the Dodgers in July for a player to be named later or cash considerations my assumption was that the return would be cash and the considerations would be approximately the cost of a bucket of baseballs. Instead they ended up getting Miguel Sulbaran, a diminutive 19-year-old left-hander with a solid track record in the low minors since signing out of Venezuela as a 16-year-old.

As one of the youngest pitchers in the Midwest League last season Sulbaran had a 2.96 ERA and 101/32 K/BB ratio in 113 innings. For comparison, top-10 prospect Jose Berrios had a 3.99 ERA and 100/40 K/BB ratio in 104 innings facing the same low Single-A hitters at the same age. Two years ago the Twins drafted Berrios with the 32nd overall pick and he has much better raw stuff, so they're hardly prospect equals, but to get any sort of useful player for Butera was shocking.

Sulbaran hasn't cracked any Baseball America or ESPN rankings, but before the trade Jonathan Mayo of MLB.com rated him as the No. 14 prospect in the Dodgers' farm system. Mayo wrote that Sulbaran "has a good feel for his low-90s fastball" and "his curveball is his best offspeed pitch and both his slider and changeup show promise." Any deal for Butera would have gotten the "great trade ... who'd we get?" treatment, but Sulbaran was a nice haul.

There was a lot of excitement surrounding Amaurys Minier when the Twins signed him out of the Dominican Republic for $1.4 million as a 16-year-old, with some people even making stretched comparisons to Miguel Sano, but last season he showed the folly of hyping every big-money teenage signing. Minier began his pro career in the rookie-level Gulf Coast League and hit just .214 with 29 strikeouts in 31 games.

The good news is that he did manage six homers in 112 at-bats, which is impressive in a league where two entire teams managed only five total homers in the 60-game schedule and the overall slugging percentage was .338. The better news is that Minier turned 18 years old in January and what he did in a 31-game debut doesn't mean much in terms of his long-term potential. Not all teenage prospects come out of the gates slugging like Sano, which is what makes Sano so special.

Minier was technically signed as a shortstop, but he'll never play there and spent last season at third base. There's no real sense in trying to analyze Minier's performance so far and his place on this list is based mostly on the money the Twins paid to sign him and the fact that just about everyone seems to agree he has the potential to be a very good hitter. It may take another year or two before there's much beyond that to analyze.

Fernando Romero signed with the Twins out of the Dominican Republic in 2011, getting $260,000 as a 16-year-old. After throwing 31 mediocre Dominican Summer League innings in 2012 he moved up to the rookie-level Gulf Coast League last year for his American debut and dominated similarly inexperienced hitters with a 1.60 ERA and 47/13 K/BB ratio in 45 innings. He held opponents to a .196 batting average, including zero homers in 181 plate appearances.

Of course, Gulf Coast League numbers are rarely accurate predictors of success, particularly when the sample size is 181 plate appearances. At the time of the signing Romero reportedly threw in the high-80s and low-90s, and he's added some velocity since then while filling out his six-foot frame a bit. Like most teenagers his fastball is ahead of his off-speed stuff and Romero hasn't shown whether he can hold up under a starter's workload yet.

In terms of long-term upside he's one of the top pitching prospects in the Twins' farm system, but my general approach to this list is to be conservative with teenagers until there's some sort of track record versus decent competition. Romero won't turn 20 years old until after this season and figures to spend the whole year pitching for rookie-level Elizabethton, putting him several seasons away from even entering into the Twins' plans.